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Mathur U, Bentley DW, Hall CB, Roth FK, Douglas RG Jr.Mathur U, et al. Among authors: roth fk.Am Rev Respir Dis. 1981 Jun;123(6):633-5. doi: 10.1164/arrd.1981.123.6.633.Am Rev Respir Dis. 1981.PMID: 7271059